Key Takeaways
- • Ken Griffin's Citadel issued an internal staff memo accusing New York City Mayor Zohran Mamdani of "ignorance and disdain" after Mamdani featured Griffin's $238 million Manhattan penthouse in a viral "tax the rich" video promoting a new pied-à-terre tax on luxury second homes.
- • Citadel's Chief Operating Officer Gerald Beeson signaled potential reconsideration of a $6 billion redevelopment project at 350 Park Avenue in Manhattan, which was projected to create 6,000 construction jobs and support 15,000 permanent mid-town jobs, citing the mayor's actions as a factor.
- • Mamdani's pied-à-terre tax targets properties valued above $5 million whose owners do not reside full-time in New York City; Griffin's penthouse—purchased in 2019 as the most expensive residential property in U.S. history—directly meets the tax threshold with his primary residence in Miami.
- • The conflict escalated when Mamdani filmed promotional content outside Griffin's penthouse on April 15, explicitly naming Griffin and citing the $238 million purchase price as a centerpiece example of the wealth-targeting policy.
- • Forbes estimates Griffin's net worth at $50.7 billion; Citadel manages approximately $69 billion in assets under management as of September 2025, making Griffin one of the nation's largest GOP political donors and hedge fund operators.
Summary
New York City Mayor Zohran Mamdani's April 15 announcement of a new pied-à-terre tax on luxury second homes escalated into a high-stakes confrontation with billionaire hedge fund founder Ken Griffin, threatening a major Manhattan development project and highlighting broader tensions between wealthy individuals and progressive urban taxation policies.
Mamdani's promotional video for the tax specifically featured Griffin's $238 million penthouse—the most expensive residential property ever sold in American history, purchased in 2019—as the centerpiece example of properties targeted by the new policy. The tax imposes an annual fee on residential properties valued above $5 million whose owners do not reside full-time in New York City. Mamdani directly named Griffin in the video, stating: "Like for this penthouse, which hedge fund CEO Ken Griffin bought for $238 million." Griffin's primary residence is located in Miami, Florida, placing his Manhattan property squarely within the tax's scope.
Griffin responded through an internal Citadel memo distributed to employees, with Chief Operating Officer Gerald Beeson directly addressing the conflict. The memo accused Mamdani of exhibiting "ignorance and disdain . . . towards those who have been consistently committed to building one of the greatest cities in the world." More significantly, Beeson indicated that Citadel's commitment to a transformative Manhattan development project—the redevelopment of 350 Park Avenue—now faces potential reconsideration. According to the Wall Street Journal, which obtained the email, Beeson wrote: "We are about to commence the redevelopment of 350 Park Avenue, creating 6,000 highly paid construction jobs and supporting the creation of more than 15,000 permanent jobs in mid-town New York. The project—if we move forward—will entail more than $6 billion dollars of spending."
The dispute also raised personal safety concerns. Critics of Mamdani's video approach noted the optics of filming outside a private residence to highlight a specific individual, with some characterizing the tactic as potentially threatening to Griffin's security and setting a problematic precedent for targeting wealthy individuals by location and identity.
Citadel, founded by Griffin in 1990, operates as one of the world's largest hedge funds with $69 billion in assets under management as of September 2025. Griffin, with an estimated net worth of $50.7 billion, has been a significant Republican political donor. The confrontation signals potential consequences for New York City's economic development agenda, as major employers weigh the political and tax climate implications of their continued Manhattan operations and investment commitments.
Mamdani's promotional video for the tax specifically featured Griffin's $238 million penthouse—the most expensive residential property ever sold in American history, purchased in 2019—as the centerpiece example of properties targeted by the new policy. The tax imposes an annual fee on residential properties valued above $5 million whose owners do not reside full-time in New York City. Mamdani directly named Griffin in the video, stating: "Like for this penthouse, which hedge fund CEO Ken Griffin bought for $238 million." Griffin's primary residence is located in Miami, Florida, placing his Manhattan property squarely within the tax's scope.
Griffin responded through an internal Citadel memo distributed to employees, with Chief Operating Officer Gerald Beeson directly addressing the conflict. The memo accused Mamdani of exhibiting "ignorance and disdain . . . towards those who have been consistently committed to building one of the greatest cities in the world." More significantly, Beeson indicated that Citadel's commitment to a transformative Manhattan development project—the redevelopment of 350 Park Avenue—now faces potential reconsideration. According to the Wall Street Journal, which obtained the email, Beeson wrote: "We are about to commence the redevelopment of 350 Park Avenue, creating 6,000 highly paid construction jobs and supporting the creation of more than 15,000 permanent jobs in mid-town New York. The project—if we move forward—will entail more than $6 billion dollars of spending."
The dispute also raised personal safety concerns. Critics of Mamdani's video approach noted the optics of filming outside a private residence to highlight a specific individual, with some characterizing the tactic as potentially threatening to Griffin's security and setting a problematic precedent for targeting wealthy individuals by location and identity.
Citadel, founded by Griffin in 1990, operates as one of the world's largest hedge funds with $69 billion in assets under management as of September 2025. Griffin, with an estimated net worth of $50.7 billion, has been a significant Republican political donor. The confrontation signals potential consequences for New York City's economic development agenda, as major employers weigh the political and tax climate implications of their continued Manhattan operations and investment commitments.
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